# ✅ Noahvelle POS Backend - Complete Setup Checklist

## Phase 1: Installation (Do This First)
- [ ] Read QUICKSTART.md from backend folder
- [ ] Start XAMPP (Apache & MySQL)
- [ ] Create database "noahvelle_pos" in phpMyAdmin
- [ ] Import schema.sql into the database
- [ ] Verify backend homepage loads at: http://localhost/Noahvelle%20POS/backend/

## Phase 2: Database Configuration
- [ ] Check database credentials in: backend/config/database.php
- [ ] Confirm MySQL host is "localhost"
- [ ] Confirm MySQL user is "root"
- [ ] Confirm MySQL password is empty (or your XAMPP password)
- [ ] Confirm database name is "noahvelle_pos"

## Phase 3: Test API Endpoints
- [ ] Test login endpoint with default admin account
- [ ] Test products endpoint (should return 6 products)
- [ ] Test customers endpoint (should return 5 customers)
- [ ] Test suppliers endpoint (should return 3 suppliers)
- [ ] Create a test transaction (sale)
- [ ] Verify transaction was saved to database

## Phase 4: Setup Logging
- [ ] Create empty "logs" folder in backend/ if not exists
- [ ] Confirm folder is writable by web server
- [ ] Test error logging by checking logs/error.log

## Phase 5: Frontend Integration
- [ ] Copy API_INTEGRATION.js to your React project
- [ ] Update API_BASE_URL in your components to match
- [ ] Test login by calling POSApiService.login()
- [ ] Test products by calling POSApiService.getAllProducts()
- [ ] Test customer operations

## Phase 6: Production Readiness
- [ ] Review SETUP.md for production settings
- [ ] Change database password (when ready)
- [ ] Update user PINs with secure values
- [ ] Plan JWT token implementation
- [ ] Review security notes in README.md
- [ ] Test CORS headers with your frontend domain
- [ ] Set up HTTPS for production
- [ ] Create automated backups

## Quick Troubleshooting Checklist

### "Cannot connect to database"
- [ ] MySQL is running in XAMPP?
- [ ] Database "noahvelle_pos" exists?
- [ ] Credentials in config/database.php are correct?
- [ ] Check backend/logs/error.log for details

### "API returns empty results"
- [ ] Database schema was imported successfully?
- [ ] Sample data is in the database?
- [ ] API_BASE_URL is correct in your frontend?
- [ ] CORS is not blocking the request?

### "CORS errors in browser console"
- [ ] CORS headers are already enabled (should work)
- [ ] Check browser console for actual error message
- [ ] Try testing with curl or Postman first
- [ ] Check Content-Type header is application/json

### "Stock not updating after sale"
- [ ] Transaction was created successfully?
- [ ] Transaction ID was returned?
- [ ] Product variation exists in database?
- [ ] Check database integrity

## File Creation Verification

### Core Files
- [ ] backend/config/database.php
- [ ] backend/config/Database.php
- [ ] backend/index.php

### API Endpoints (7 files)
- [ ] backend/api/auth.php
- [ ] backend/api/products.php
- [ ] backend/api/customers.php
- [ ] backend/api/transactions.php
- [ ] backend/api/suppliers.php
- [ ] backend/api/expenses.php
- [ ] backend/api/promotions.php

### Models (7 files)
- [ ] backend/models/User.php
- [ ] backend/models/Product.php
- [ ] backend/models/Customer.php
- [ ] backend/models/Transaction.php
- [ ] backend/models/Supplier.php
- [ ] backend/models/Expense.php
- [ ] backend/models/Promotion.php

### Helper & Config
- [ ] backend/includes/cors.php
- [ ] backend/includes/POSHelper.php
- [ ] backend/.htaccess

### Documentation (5 files)
- [ ] backend/QUICKSTART.md
- [ ] backend/SETUP.md
- [ ] backend/README.md
- [ ] backend/ARCHITECTURE.md
- [ ] backend/API_INTEGRATION.js

### SQL & Logs
- [ ] backend/sql/schema.sql (16 tables)
- [ ] backend/logs/index.php

### Root Summary
- [ ] BACKEND_SUMMARY.txt (in root)

## Database Verification

### Tables Created (16)
- [ ] users (3 default users)
- [ ] customers (5 default customers)
- [ ] categories (5 categories)
- [ ] products (6 default products)
- [ ] products_variations
- [ ] transactions
- [ ] transaction_items
- [ ] credit_notes
- [ ] returns
- [ ] suppliers (3 default suppliers)
- [ ] supplier_payments
- [ ] expenses
- [ ] promotions (4 default promotions)
- [ ] promotion_products
- [ ] customer_loyalty
- [ ] Total: 16 tables ✓

### Sample Data Loaded
- [ ] 3 users (admin, cashier1, cashier2)
- [ ] 5 customers
- [ ] 6 products
- [ ] 5 categories
- [ ] 3 suppliers
- [ ] 4 promotions

## API Endpoints Count
- [ ] Auth: 4 endpoints
- [ ] Products: 6 endpoints
- [ ] Customers: 7 endpoints
- [ ] Transactions: 4 endpoints
- [ ] Suppliers: 6 endpoints
- [ ] Expenses: 5 endpoints
- [ ] Promotions: 5 endpoints
- [ ] **Total: 37+ endpoints** ✓

## Security Checklist (Before Production)

### Immediate
- [ ] Change default user PINs
- [ ] Update database password
- [ ] Review database.php settings
- [ ] Enable error logging

### Short Term
- [ ] Implement JWT token authentication
- [ ] Replace MD5 with bcrypt for passwords
- [ ] Add input validation on all endpoints
- [ ] Enable HTTPS only

### Medium Term
- [ ] Set up automated backups
- [ ] Implement rate limiting
- [ ] Add API versioning
- [ ] Create audit logging
- [ ] Set up monitoring/alerts

## Documentation Checklist
- [ ] Read QUICKSTART.md (5 min)
- [ ] Read SETUP.md (10 min)
- [ ] Review README.md (reference)
- [ ] Study ARCHITECTURE.md (design)
- [ ] Implement API_INTEGRATION.js patterns

## Testing Checklist

### Manual Testing
- [ ] Test login with default accounts ✓
- [ ] Create a customer ✓
- [ ] Create a sale/transaction ✓
- [ ] View transaction details ✓
- [ ] Check stock was updated ✓
- [ ] Create an expense ✓
- [ ] Create a supplier payment ✓

### API Testing Tools
- [ ] Use Postman for API testing
- [ ] Use curl for command-line testing
- [ ] Use browser DevTools for frontend testing

### Database Testing
- [ ] Verify data in phpMyAdmin
- [ ] Check relationships between tables
- [ ] Verify foreign keys work
- [ ] Test transaction atomicity

## Performance Checklist
- [ ] API response time < 200ms
- [ ] Database indexes are properly set
- [ ] No N+1 queries
- [ ] Connection pooling configured
- [ ] Caching strategy planned

## Documentation Status
- [ ] Backend created ✓
- [ ] All endpoints documented ✓
- [ ] Integration guide provided ✓
- [ ] Setup guide created ✓
- [ ] Architecture documented ✓
- [ ] Troubleshooting guide included ✓
- [ ] Quick start guide written ✓

## Final Verification Steps

1. **Database Connection**
   ```bash
   mysql -u root -p
   USE noahvelle_pos;
   SHOW TABLES;  # Should show 16 tables
   SELECT COUNT(*) FROM users;  # Should show 3
   SELECT COUNT(*) FROM products;  # Should show 6
   ```

2. **API Server**
   - [ ] http://localhost/Noahvelle%20POS/backend/ returns JSON
   - [ ] http://localhost/Noahvelle%20POS/backend/api/auth.php returns error (no action)
   - [ ] All endpoints are accessible

3. **Frontend Integration**
   - [ ] API_INTEGRATION.js is available
   - [ ] React app can fetch from API
   - [ ] Authentication works
   - [ ] CORS is properly configured

## Go-Live Checklist

Before moving to production:
- [ ] All tests pass
- [ ] Performance is adequate
- [ ] Security review completed
- [ ] Backup strategy in place
- [ ] Monitoring configured
- [ ] Team trained on API
- [ ] Documentation finalized
- [ ] Load testing completed

## Support & Maintenance

### Regular Tasks
- [ ] Monitor error logs weekly
- [ ] Backup database daily
- [ ] Check for PHP updates
- [ ] Review API usage statistics
- [ ] Update PINs periodically

### When Issues Arise
1. Check backend/logs/error.log
2. Review browser console (F12)
3. Test with Postman first
4. Check database with phpMyAdmin
5. Review TROUBLESHOOTING section in SETUP.md

## Success Criteria

- [ ] Database is running and connected
- [ ] All 37+ API endpoints are working
- [ ] Sample data is loaded
- [ ] Frontend can communicate with backend
- [ ] Transactions are being recorded
- [ ] Stock is being updated
- [ ] No errors in logs
- [ ] Performance is acceptable

---

## 🎉 YOU'RE ALL SET!

Once you've completed this checklist, your Noahvelle POS backend is ready for development and testing!

**Next Steps:**
1. Start XAMPP
2. Create & import database
3. Test APIs with Postman
4. Integrate with React frontend
5. Deploy to production

**Questions?** Check the documentation files in `backend/`

**Happy coding!** 🚀
